Electrical connector



Oct. 27, 1964 R. A. GERG 3,154,364

ELECTRICAL CONNECTOR Filed April 24, 1961 v/wkoh @ip v Q S M -5' fi Mxmwhammy;

United States Patent M 3,154,364 ELECTRICAL CONNECTGR Robert A. Gerg,Brookfield, Wis, assignor to Allis- Chalmers Manufacturing Company,Milwaukee, Wis. Filed Apr. 24, 1961, Ser. No. 104,960 4 Claims. (Cl.339176) This invention relates generally to electrical connectors. Morespecifically this invention relates to electrical connectors of the typehaving two members of insulating material, each of which carries aplurality of independent contacts arranged so that the contacts of onemember fn'ctionally engage the contact members of the other member whenthey are coupled together.

The type of electrical connector described above have become known inthe art as plug-in terminal blocks. It is common to have these terminalblocks located in shelflike compartments within a large enclosure. Thesize of these compartments usually limits the amount of space for theseterminal blocks to a relatively small value. However, good frictionalengagement between the contacts is required to insure continuedelectrical communication under all operating conditions. Because of thestrong frictional engagement between the contacts and the limited spacein the compartments extreme difiiculty has been encountered indisconnecting these terminal blocks.

If an operator tried to lift the top portion of the connector off in avertical direction, considerable force was required and his handsfrequently moved rapidly away from the base when the frictional holdingforce was released as the contacts separated. Because of the crowdedconditions in the compartment where the connector is located theoperator often hit his hands and fingers against the frame of thecompartment or other equipment in the compartment causing injury to theoperator. Frequently the operator would use a tool to separate thehalves of the connector. Usually this tool was inserted underneath theupper half and used to pry it away from the base. Normally one end ofthe movable portion of the connector would move upward while the otherend remained in close contact with the base. This had the effect ofbending the contacts of the connectors. In many cases the contacts werebent to such an extent that they were not reusable or were extremelyhard to reassemble.

The terminal block of this invention overcomes the problems as mentionedabove by providing a fulcrum member or projection near the edge of theterminal block around which the upper half of the block pivots as it isbeing engaged or disengaged. The fulcrum member is located to give ahigh mechanical advantage when exerting a force at the top of theconnector and to allow the disconnecting force to be exerted in anoutward rather than upward direction. Furthermore, the fulcrum member ipositioned so that the engaging contacts tend to be withdrawn orseparated from each other along a plane substantially parallel to thecontact engaging surfaces. This reduces the tendency to bend the uprightcontact members. Hence, not only is it easier and safer to remove theupper part of the terminal block but it reduces the deformation of thecontacts and thus increases the overall life of the connectors.Furthermore, since the contacts in the lower half of the connector arenot bent it is much easier to reassemble the connector when utilizingthe design of this invention.

Therefore, it is the object of this invention to provide a new andimproved electrical connector.

Another object of this invention is to provide a new and improvedelectrical connector that is easier to connect and disconnect.

3,154,354 Patented Oct. 27, 1964 Another object of this invention is toprovide a new and improved electrical connector that is safer tooperate.

Another object of this invention is to provide a new and improvedelectrical connector that has a longer life.

Other objects and advantages of this invention will be apparent from thefollowing description when taken in connection with the accompanyingdrawings, in which:

FIG. 1 is a front view of an electrical connector of this invention;

FIG. 2 is an exploded end view of the connector of FIG. 1 taken alongthe line lll1;

P16. 3 is a rear view of the connector of FIG. 1; and

FIG. 4 is a top view of the base of the connector in the orientation ofFIG. 3.

Referring generally to the drawings, the electrical connector it) ofthis invention comprises a base 11 and a movable member 12 each of whichis made of insulating material and has a plurality of contact members.The base 11 which would normally be the lower portion is provided with aprojection at one end which can be referred to as a fulcrum member 14.The peak of the fulcrum member is removed a significant distance fromthe top of the movable member to which the disengaging force would beapplied to provide a near maximum mechanical advantage. The movable partof the connector is provided with a suitable recess 15 or cam surfacethat engages and cooperates with the fulcrum member.

More specifically, the base 11 has a frame 16 made of a suitableelectric insulating material and is provided with a plurality ofspaced-apart contacts 17. The contacts have substantially flat engagingsurfaces 18 and are mounted on the frame 16 in any suitable manner as iswell known in the art. Preferably the contact-engaging surfaces 18 aresubstantially rectangular in form as shown in FIG. 2 and are riveted tothe frame. As shown in FIG. 1 the contacts form a closed rectangle andbecome the male contacts of the connector.

The base 11 has a number of grooves 21 formed in the frame 16intermediate the contacts 17. The grooves 21 as shown in FIG. 1 run in adirection that is substantially parallel to the engaging surfaces 18 ofthe contacts. Suitable means may be provided for mounting the base to athe base on a fixture.

One side of the frame 16 has the fulcrum member 14 formed thereon. Asbest shown in FIG. 3 this fulcrum member 14 is spaced from contact 17and extends across the one edge on the side of the frame 16 thatnormally faces outward from the compartment in which it is positioned.In the preferred embodiment as illustrated, a plurality of grooves 33are formed in the fulcrum member 14. As FIG. 4 shows, grooves 30 are incommunica tion With associated grooves 21 in the frame 16 and combine toform means for locating the movable body 12 of the connector relative tothe base 11. Furthermore, the inner surface 31 of the fulcrum member isinclined inward toward the contact members 17. This inclined surfaceforms a convenient guide for assembling and mating the separate portionsof the connector.

The movable member 12 of the connector is made up of a body 35 ofsuitable insulation material and has a plurality of contacts 36 arrangedto engage the contacts 17 on the base. As shown in FIG. 1 these contacts3t: are made up in sets 37 or pairs of spaced-apart prongs 38. The setsof prongs 38 are separated by a projection or Wall 40 of insulatingmaterial. These projections 40 serve as are barriers and are designed tofit into associated grooves 21 in the base 11 to properly locate thecontacts 36 of the movable member 12 relative to the contacts 17 of thebase 11. The sets of prongs 38 form the female contacts of the connector10. However, it would be apparent to anyone skilled in the art that thecontacts could be reversed without departing from the spirit of theinvention.

One side of the body 35 has a recess portion formed therein forreceiving the fulcrum member 14 as described above. The inner surface 44of the recess defining portion is inclined or tapered complementary tothe tapered surface 31 of the fulcrum member 14.

In a connector of this type, the movable part is disengaged by exertinga force in an outward direction at the top of the movable member.Therefore, to obtain a maximum mechanical advantage the fulcrum memberis located as close as possible to the parting line of the movable andstationary members and as far as practical from the point where thedisconnect force is applied. Therefore, the recess portion of themovable member is located at the greatest distance from the top of themember as is compatible with good design standards. However, in thisconnector the fulcrum member 14 also serves as a guide for assemblingthe base 11 and movable member 12 of the connector and has the furtherfunction of acting as a buffer between the movable member and thestationary contacts 17. If there were no fulcrum member and the partingsurface of the connector were completely flat, When the upper member wasbeing pivoted away, the pivot point or line would slide inward until itreached the stationary contacts and a large portion of the disengagingforce would be transmitted through the movable member 12 directly to thestationary contacts. However, in applicants construction, when themovable member is pivoted out of engagement with the stationary member,the disengaging force is exerted on the fulcrum member 14 which is apart of the frame 16 of the stationary member. Hence, none of thedisengaging force is exerted directly on the stationary contacts. Thisfeature of the connector is important because undue force on thecontacts 17 may dislodge the contacts from the frame '16 and move themout of alignment with the prongs 38 of the contacts 36 on the movablemember.

In operation the base 11 is normally attached to the frame of acompartment in a control center or others by inserting bolts through theholes 24 in the flanges 23. The wires in the stationary control centerare then connected up to appropriate contacts in the base. Theelectrical connections are made to the contacts 36 of the movable memberof the connector. The movable member is then connected to the base byplacing the body against the fulcrum member 14 so that the recessportion 15 fits over the fulcrum member with the projections 4fpositioned in their associated grooves 39. The movable member 12 is thenpivoted around the fulcrum member and the projections 40 slide into thegrooves 21 in the base and guide the prongs 38 of movable contacts 36into engagement with the surfaces 18 of the stationary contacts 17. Theinclined surface 31 of the fulcrum member 14 cooperates with theinclined surface 44 of the movable member .to further align the contactengaging surfaces 18 that are parallel to the grooves 21. By using boththe complementary inclined surface of the fulcrum member 14 and grooves21 and projection 40, the contacts are aligned and fitted so as toassure the maximum amount of surface contact between the stationary andmovable contacts 17, 36.

When it is desired to disengage the connector an out Ward force isexerted at the top of the movable member. The movable member then pivotsoutward around the fulcrum member until the contacts 17, 35 disengage.Then the movable member is pulled away from the base and out of thecompartment in the control center.

Although but one embodiment has been illustrated and described, it willbe apparent to those skilled in the art that various changes andmodifications may be made therein without departing from the spirit ofthe invention or from the scope of the appended claims.

Having now particularly described and ascertained the nature of my saidinvention and the manner in which it is to be performed, I declare thatwhat I claim is:

1. An electrical connector comprising, a base of insulating materialhaving a-plurality of spaced apart sets of male electrical contactsmounted therein, said base being adapted to be mounted on a supportingsurface, each of said contacts having a pair of substantially parallelengaging surfaces, a fulcrum member comprising a ridge extending alongone edge of said base substantially perpendicular to the said engagingsurfaces of said contacts, said base having grooves intermediate eachset of contacts, said fulcrum member having grooves formed thereincommunicating with said grooves in said base, a body of electricalinsulation having a plurality of sets of female contacts arranged toengage complementary contact surfaces in said base, barriers interposedbetween said sets of contacts and adapted to fit into associated groovesin said base to locate said male contacts relative to said femalecontacts, said body having a recess portion for receiving said fulcrummember, whereby said contacts can be engaged or disengaged by pivotingsaid body relative to said base.

2. An electrical connector comprising, a base of insulating materialhaving a plurality of spaced apart sets of male electrical contactsmounted therein, said base being adapted to be mounted on a supportingsurface, each of said contacts having a pair of substantially parallelengaging surfaces, a fulcrum member comprising a ridge extending alongone edge of said base substantially perpendicular to the said engagingsurfaces of said contacts, said base having grooves intermediate eachset of contacts, said fulcrum member having grooves formed thereincommunicating with said grooves in said base,

- one surface of said fulcrum member being tapered inward toward saidcontacts a body of electrical insulation having a plurality of sets offemale contacts arranged to engage complementary contact surfaces insaid base, barriers interposed between said sets of contacts and adaptedto fit into associated grooves in said base to locate said male contactsrelative to said female contacts, said body having a recess portion forreceiving said fulcrum member, one surface of said recess portion beingtapered complementary to the tapered surface of said fulcrum member forguiding said body into proper engagement with said base.

3. An electrical connector comprising, a base of insulating materialhaving a plurality of spaced apart sets of male electrical contactsmounted therein, said base being adapted to be mounted on a supportingsurface, each of said contacts having a pair of substantially parallelengaging surfaces, a fulcrum member comprising a ridge extending alongone edge of said base substantially perpendicular to and spaced from thesaid engaging surfaces of said contacts, said base having groovesintermediate each set of contacts, said fulcrum member having groovesformed therein communicating with said grooves in said base, one surfaceof said fulcrum member being tapered inward toward said contacts, a bodyof electrical insulation having a plurality of sets of female contactsarranged to engage complementary contact surfaces in said base, barriersinterposed between said sets of contacts and adapted to fit intoassociated grooves in said base to locate said male contacts relative tosaid female contacts, said body having a recess portion for receivingsaid fulcrum member, one surface of said recess portion being taperedcomplementary to the tapered surface of said fulcrum member for guidingsaid body into proper engagement with said base.

4. An electrical connector comprising, a base of insulating materialhaving a plurality of spaced apart sets of male electrical contactsmounted therein, each of said contacts having a pair of substantiallyparallel engaging surfaces, a fulcrum member comprising a ridgeextending along one edge of said base substantially perpendicular to andspaced from the said engaging surfaces of said confacts, said basehaving grooves intermediate each set of contacts, said fulcrum memberhaving grooves formed therein communicating with said grooves in saidbase, one surface of said fulcrum member being tapered inward towardsaid contacts, said base haw'ng extensions for mounting said base to asupport structure, a body of electrical insulation having a plurality ofsets of female contacts arranged to engage complementary contactsurfaces in said base, barriers, interposed between said sets ofcontacts and adapted to fit into associated grooves in said base tolocate said male contacts relative to said female contacts, said bodyhaving a recess portion for receiving said fulcrum member, one surfaceof said recess References Cited in the file of this patent UNITED STATESPATENTS 2,441,393 Buchanan et al May 11, 1948 2,787,773 Potter Apr. 2,1957 2,899,669 Johanson Aug. 11, 1959 2,914,708 Edmunds Nov. 24, 19592,923,911 Demurjian Feb. 2, 1960 3,048,806 Heidler Aug. 7, 1962

1. AN ELECTRICAL CONNECTOR COMPRISING, A BASE OF INSULATING MATERIALHAVING A PLURALITY OF SPACED APART SETS OF MALE ELECTRICAL CONTACTSMOUNTED THEREIN, SAID BASE BEING ADAPTED TO BE MOUNTED ON A SUPPORTINGSURFACE, EACH OF SAID CONTACTS HAVING A PAIR OF SUBSTANTIALLY PARALLELENGAGING SURFACES, A FULCRUM MEMBER COMPRISING A RIDGE EXTENDING ALONGONE EDGE OF SAID BASE SUBSTANTIALLY PERPENDICULAR TO THE SAID ENGAGINGSURFACES OF SAID CONTACTS, SAID BASE HAVING GROOVES INTERMEDIATE EACHSET OF CONTACTS, SAID FULCRUM MEMBER HAVING GROOVES FORMED THEREINCOMMUNICATING WITH SAID GROOVES IN SAID BASE,